18 F-FDG and 68 Ga-FAPI-04 PET/CT Imaging in a Patient With Hepatocellular Carcinoma After 90 Y-SIRT.

The 18 F-FDG and 68 Ga-FAPI-04 PET/CT imaging findings were reported in a 52-year-old man with hepatocellular carcinoma (HCC) 3 weeks after undergoing yttrium-90 selective internal radiation therapy ( 90 Y-SIRT). Both viable tumors and tumor thrombus of right portal vein showed mild-to-moderate 18 F-FDG uptake, while peritumoral tissues showed high 68 Ga-FAPI-04 uptake, the range of which approximately matched radiotracer distribution on 90 Y SPECT/CT. Our findings indicate that 18 F-FDG PET/CT is superior to 68 Ga-FAPI-04 PET/CT for identifying viable HCC tumors during early 90 Y-SIRT monitoring, whereas 68 Ga-FAPI-04 PET/CT indirectly delineates the area of 90 Y-SIRT.